audio: host: remove duplicated calculation for sample bytes

in parameter, dma sample bytes already was calculated and assigned
to dma config, during copy, this can be directly used, cycle saving
is quite remarkable, 452 to 425, previous target is 420, we already
meet with this patch.

note: test platform is tgl board with sof debug build.

Signed-off-by: Baofeng Tian <baofeng.tian@intel.com>

src/audio/host-zephyr.c

@@ -374,7 +374,6 @@ static uint32_t host_get_copy_bytes_normal(struct host_data *hd, struct comp_dev
 {
  struct comp_buffer *buffer = hd->local_buffer;
  struct comp_buffer *buffer_c;
- struct comp_buffer *dma_buf_c;
  struct dma_status dma_stat;
  uint32_t avail_samples;
  uint32_t free_samples;
@@ -391,9 +390,7 @@ static uint32_t host_get_copy_bytes_normal(struct host_data *hd, struct comp_dev
  return 0;
  }
 
- dma_buf_c = buffer_acquire(hd->dma_buffer);
- dma_sample_bytes = get_sample_bytes(audio_stream_get_frm_fmt(&dma_buf_c->stream));
- buffer_release(dma_buf_c);
+ dma_sample_bytes = hd->config.src_width;
 
  buffer_c = buffer_acquire(buffer);